1. Field of the Invention
This invention relates to quaternary ammonium compounds in which the ammonium nitrogen atom carries one or two long-chain ester groups or amide groups of etherified hydroxycarboxylic acids, to a process for the production of these quaternary ammonium compounds, and to their use in fabric aftertreatment preparations.
Quaternary ammonium compounds containing one or two long-chain and three or two short-chain aliphatic hydrocarbon radicals in the molecule, such as for example the compound distearyldimethylammonium chloride, have long been used as fabric softeners for the treatment of fabrics, more especially for the aftertreatment of washed laundry, but also in softening detergents and in tumbler aids. By treatment with compounds of this type, the fabrics, drying-up cloths or diapers, which have been repeatedly treated with quaternary ammonium compounds of the type in question after washing, show impaired service properties on account of their reduced or retarded water absorption capacity. These unfavorable effects are attributable to the fact that the quaternary ammonium compounds applied to the fibers are not removed or are not completely removed during the subsequent washing process, so that repeated aftertreatment results in an accumulation of the quaternary ammonium compounds on the fibers of the fabrics.
2. Discussion of Related Art
Through various measures which have been mainly concerned with increasing the hydrophilicity of the softening compounds, attempts have been made to reduce or completely eliminate the above-mentioned disadvantages of known fabric softeners. For example, hydroxyl groups have been introduced into one or more of the long-chain or short-chain groups of the quaternary compounds or the long-chain groups used have been those wherein the hydrocarbon is interrupted, for example, by ether, amide or ester groups. Thus, German Patent Appplication 16 19 058 for example describes quaternary ammonium compounds derived from methyl diethanolamine wherein the ethanol groups are esterified with saturated or unsaturated monocarboxylic acids. European Patent Application 21 431 describes quaternary ammonium compounds wherein the hydrocarbon chains contain ester, ether, ethoxy or propoxy groups.
German Patent Application 34 02 146 relates to quaternary ammonium compounds containing one or two long-chain ester groups wherein the acid component is derived from branched carboxylic acids of the so-called "Guerbet" type.
Although the quaternary ammonium compounds known from German Patent Application 34 02 146 have few, if any, of the above-described disadvantages, they can only be produced in several complicated process steps or accumulate during their production in the form of dilute dispersions which cannot be used for the production of the fabric softener concentrates in which increasing interest has been shown in recent years. In addition, they are attended by the disadvantages that they are difficult to dissolve or disperse in aqueous systems or show a tendency towards hydrolysis therein. Those compounds which contain ester bonds are particularly affected by this disadvantage.
An object of the present invention is to provide raw materials for fabric aftertreatment preparations which do not have the disadvantages of the prior art. The invention seeks to provide raw materials for fabric aftertreatment preparations which, in addition to good solubility in aqueous preparations which, in addition to good solubility in aqueous systems, are also suitable for blending into concentrates for fabric aftertreatment preparations. In view of the high demand for concentrates such as these, the so-called "ten-fold concentrates" are of particular interest. In addition, the raw materials for fabric aftertreatment preparations are also intended to bring with them the property of not affecting the absorbency of the treated fabrics, so that the treated fabrics fully retain their absorbency even after repeated washing and aftertreatment. So far as the production of the raw materials for fabric aftertreatment preparations is concerned, the invention seeks to use only those raw materials which are available from natural sources and hence are capable of regeneration.